U.S. patent application number 10/404251 was filed with the patent office on 2004-09-30 for ventable storage bag.
Invention is credited to Borchardt, Michael, Giesfeldt, Rebecca, Hamilton, Peter, McGuire, Kenneth S..
Application Number | 20040188310 10/404251 |
Document ID | / |
Family ID | 32990130 |
Filed Date | 2004-09-30 |
United States Patent
Application |
20040188310 |
Kind Code |
A1 |
Hamilton, Peter ; et
al. |
September 30, 2004 |
Ventable storage bag
Abstract
A storage bag for food products with a venting structure to
expel excess air trapped inside the bag after the bag has been
closed or sealed. After the excess air is removed, the venting
structure is covered and sealed to prevent air from re-entering the
bag or other objects from entering the bag.
Inventors: |
Hamilton, Peter;
(Cincinnati, OH) ; Borchardt, Michael;
(Naperville, IL) ; Giesfeldt, Rebecca; (Chicago,
IL) ; McGuire, Kenneth S.; (Cincinnati, OH) |
Correspondence
Address: |
THE CLOROX COMPANY
1221 BROADWAY #2351
OAKLAND
CA
94612
US
|
Family ID: |
32990130 |
Appl. No.: |
10/404251 |
Filed: |
March 31, 2003 |
Current U.S.
Class: |
206/524.8 |
Current CPC
Class: |
B65D 33/2508 20130101;
B65D 33/01 20130101; B65D 2205/025 20130101 |
Class at
Publication: |
206/524.8 |
International
Class: |
B65D 081/20 |
Claims
1. A ventable bag for storing products comprising: front and back
walls joined at opposing sides and defining a storage space with a
closed bottom end and a top end; a re-sealable closure mechanism
being operative to selectively open and close said top end; one or
more first perforations located in said front wall proximate to
said top end and between said closure mechanism and said closed
bottom end; a cover positioned over said one or more first
perforations; and a pressure sensitive adhesive operative to
removably seal a portion of said cover to said bag; wherein said
one or more perforations permit air to be expelled from said
storage space upon at least partial removal of said cover from said
bag.
2. The bag according to claim 1 wherein said cover has a top edge,
a bottom edge, and two side edges, wherein said top edge and said
two side edges of said cover are secured to said bag and at least a
portion of said adhesive is positioned below said one or more first
perforations.
3. The bag according to claim 2 wherein said cover is a separate
piece from said bag.
4. The bag according to claim 2 wherein said adhesive is a material
capable of sealing more than once.
5. The bag according to claim 4 wherein said adhesive is positioned
on a surface of said cover facing said front wall.
6. The bag according to claim 4 wherein said adhesive is positioned
on said front wall of said bag.
7. The bag according to claim 2 wherein part of said portion of
said adhesive is positioned at said bottom edge.
8. The bag according to claim 2 wherein said bottom edge is secured
to said bag and one or more second perforations are located in said
cover between said adhesive and said bottom edge.
9. The bag according to claim 2 wherein said first perforations are
configured in a substantially straight line parallel to said
closure mechanism.
10. The bag according to claim 9 wherein said straight line is
oriented along the machine direction of said bag.
11. The bag according to claim 9 wherein said straight line is
oriented along the transverse direction of said bag.
12. The bag according to claim 1 wherein said cover has a top edge,
a bottom edge, and two side edges, wherein said bottom edge and
said two side edges of said cover are secured to said bag and at
least a portion of said adhesive is positioned between said one or
more first perforations and said top edge.
13. The bag according to claim 12 wherein said cover is a separate
piece from said bag.
14. The bag according to claim 13 wherein said adhesive is a
material capable of sealing more than once.
15. The bag according to claim 12 wherein part of said first
portion of said adhesive is positioned at said top edge.
16. The bag according to claim 15 wherein said adhesive is
positioned on a surface of said cover facing said front wall.
17. The bag according to claim 15 wherein said adhesive is
positioned on said front wall of said bag.
18. The bag according to claim 12 further including one or more
second perforations located in said cover between said adhesive and
said top edge.
19. The bag according to claim 18 wherein said top edge is secured
to said bag.
20. The bag according to claim 1 wherein said cover has a top edge,
a bottom edge, and two side edges, wherein said two side edges of
said cover are secured to said bag, a first portion of said
adhesive is positioned between said one or more first perforations
and said top edge and a second portion of said adhesive is
positioned between said one or more first perforations and said
bottom edge.
21. The bag according to claim 20 wherein part of said first
portion of said adhesive is positioned at said top edge and part of
said second portion of said adhesive is positioned at said bottom
edge.
22. The bag according to claim 1 wherein said cover is an integral
extension of said front wall of said bag.
23. The bag according to claim 22 wherein said cover has a bottom
edge and two side edges, wherein said two side edges of said cover
are secured to said bag and at least a portion of said adhesive is
positioned between said one or more first perforations and said
bottom edge.
24. The bag according to claim 23 wherein part of said second
portion of said adhesive is positioned at said bottom edge.
25. The bag according to claim 24 further including one or more
second perforations located in said cover between said adhesive and
said bottom edge.
26. The bag according to claim 25 wherein said bottom edge is
secured to said bag.
27. The bag according to claim 22 wherein said cover has a top
edge, a bottom edge and two side edges, wherein said top edge of
said cover forms a fold line between said cover and said bag, said
bottom edge and said two side edges of said cover are secured to
said bag, at least a portion of said adhesive is positioned above
said one or more first perforations, and one or more second
perforations are located between said adhesive and said top
edge.
28. The bag according to claim 27 wherein said one or more second
perforations are disposed along said fold line.
29. The bag according to claim 1 wherein said adhesive is disposed
next to said one or more perforations but not over said one or more
perforations, whereby a peel angle is formed when said air being
expelled from said storage space impinges said pressure sensitive
adhesive.
30. The bag according to claim I wherein said cover has a top edge
secured to said bag, a bottom edge secured to said bag, a first
side edge secured to said bag, and a second side edge, and a
portion of said adhesive is disposed between said first
perforations and said second side edge.
31. The bag according to claim 1 wherein said closure mechanism is
selected from the group consisting of an interlocking closure, a
closure adhesive material, and a hook and loop fastener.
32. The bag according to claim 1 wherein at least one of said first
perforations is in a C-shape, an X-shape, a cross shape, or in a
disconnected circle shape.
33. The bag according to claim 1 wherein said air is expelled from
said storage space having an exit pressure large enough to unseal
said adhesive and thereby separate said portion of said cover from
said bag.
34. A bag for storing products comprising: front and back walls
joined at opposing sides and defining a storage space with a closed
bottom end and a top end; a re-sealable closure mechanism being
operative to selectively open and close said top end; one or more
perforations provided in said front wall for permitting air trapped
within said storage space to escape, said one or more first
perforations located between said closure mechanism and said closed
bottom; a cover positioned over said one or more first perforations
for sealing said bag after air trapped within said storage space
has escaped, wherein said cover is formed as an integral extension
of said front wall of said bag, said cover comprises a terminal
edge and two side edges, said two side edges of said cover are
secured to said front wall of said bag, said terminal edge being
located between said one or more perforations and said closed
bottom end; and an adhesive for securing at least a portion of said
cover to said front wall.
35. The bag according to claim 34 wherein at least a portion of
said adhesive is positioned to directly overlay said one or more
perforations.
36. A bag for storing products comprising: front and back walls
joined at opposing sides and defining a storage space with a closed
bottom end and a top end; a re-sealable closure mechanism being
operative to selectively open and close said top end; one or more
first perforations provided in said front wall for permitting air
trapped within said storage space to escape, said one or more first
perforations located between said closure mechanism and said closed
bottom end; a cover positioned over said one or more first
perforations for sealing said bag after air trapped within said
storage space has escaped, wherein said cover is formed as an
integral extension of said front wall of said bag, said cover
comprises a terminal edge and two side edges, and said terminal
edge and two side edges of said cover are secured to said front
wall of said bag, said secured terminal edge being located between
said one or more first perforations and said closed bottom end; an
adhesive for securing at least a portion of said cover to said
front wall, said adhesive positioned between said one or more first
perforations and said top end of said bag; and one or more second
perforations disposed in said cover between said adhesive and said
closure mechanism.
37. The bag according to claim 36 wherein said adhesive is a
material capable of sealing more than once.
38. A bag for storing products comprising: a front wall, a back
wall, and a storage space defined between said front wall and said
back wall; an opening at a top of said bag for inserting products
in to said storage space; a closure mechanism disposed near said
top of said bag for closing said opening; one or more first
perforations located in said front wall proximate to said opening
and beneath said closure mechanism for permitting air trapped
within said storage space to escape; a cover positioned over said
one or more first perforations for sealing said bag after air
trapped within said storage space has escaped, wherein said cover
is a separate piece from said bag, said cover comprises a top edge,
a bottom edge, and two side edges, and said top edge and said
bottom edge of said cover are secured to said bag; a pressure
sensitive adhesive disposed between said top edge and said one or
more first perforations; and one or more second perforations
disposed between said adhesive and said top edge.
39. The bag according to claim 38 wherein a portion of said
adhesive is positioned directly on top of said first
perforations.
40. A method of expelling air trapped inside a storage bag
comprising the steps of: providing one or more perforations in a
front wall of said bag for said trapped air to exit said bag;
providing a releasable seal between said cover and said front wall;
providing an opening to atmosphere for said trapped air after said
breaking of the releasable seal; applying external pressure to a
surface of said bag whereby said trapped air exits said bag through
said one or more perforations, whereby said releasable seal is
released by said air exiting said bag; and resealing said cover to
said front wall by applying external pressure to said cover over
said releasable seal.
41. The method according to claim 40 wherein the step of providing
a releasable seal comprises providing an adhesive directly over
said perforations.
42. The method according to claim 40 wherein the step of providing
a releasable seal comprises providing an adhesive away from said
perforations.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to storage bags and
specifically to a ventable storage bag for expelling unwanted air
trapped internally by the bag.
BACKGROUND OF THE INVENTION
[0002] Storage bags are a common household product used throughout
the world. Storage bags are conventionally used to store food
products in a refrigerator, freezer, portable cooler for camping,
picnics, backyard barbecues, or similar type occasions, or even in
kitchen cabinets. Stored food items may include, for example,
fruits, deli meats, poultry, bread, cheese, beef, sauces, chips,
nuts, sugar, flour, and the like. Storage bags may also be used to
store various other items such as cosmetic applicators, personal
care items, pills, screws or nails, batteries, and the like. Such
bags are often made of a flexible material such as plastic, and
therefore may be preferred for storage use over a hard-sided
container. That is because the size of the flexible bag may be
adjusted to match the space required to store the bag's contents,
whereas if a hard-sided container is only half full, the empty half
is just wasted space.
[0003] One difficulty with conventional storage bags is air can get
trapped inside the bag as the user closes the bag. This decreases
the shelf-life or storage longevity of a stored product.
Particularly, when the storage bag stores a food product and is
placed in a freezer, excess air in the bag may cause desiccation
(commonly known as freezer burn) thus spoiling the stored food
product. Some persons have tried to solve the problem of unwanted,
excessive air inside a storage bag by vacuum sealing the bag. This
process requires a machine to vacuum or pump the excess air out of
the bag and may take up to several minutes to seal each bag. The
machine, while taking up a great deal of counter-top or kitchen-top
space, creates noise. In addition, conventional vacuum sealing
machines can be expensive and thus may not be affordable to the
average consumer.
[0004] Another problem with storage bags is that the air trapped
inside a bag increases the size of the bag, therefore taking up
more space in the refrigerator, freezer, cooler, shelf, or box that
is strictly required to store the contents of the bag. For a user
with limited storage space or a shipping company that wants to
maximize storage space use, and therefore profits, unnecessary air
inside the storage bag is undesirable. This problem may be resolved
only with complicated, and time consuming, manipulation of the bag
to squeeze out the air as the bag is closed.
[0005] It has been known to utilize a package valve in an attempt
to overcome these or similar problems. Many of these prior valves,
however, are difficult and expensive to manufacture in that
multiple pieces must be made, handled, and assembled. As will be
understood to one of ordinary skill, storage bags may conveniently
be manufactured by sealing and cutting a continuous plastic web as
it is formed at high speeds. At such high speeds, placing a valve
in the bags in a consistent position presents several technical
difficulties. Inevitably this will require a slower moving web, as
well as complicate the manufacturing process, leading to reduced
production capacity at an increased cost. Exemplary package valves
are disclosed in U.S. Pat. No. 3,432,087 to Costello.
[0006] Accordingly, it would be beneficial to have a storage bag
that is cost efficient to make and use, easy to manufacture,
increases the shelf or storage life of a stored product, conserves
space and is easy to use.
SUMMARY OF THE INVENTION
[0007] The present invention is a bag for storing products with a
front wall, a back wall, and a storage space defined between the
front wall and the back wall. The bag includes an opening at a top
of the bag with a closure mechanism. One or more first perforations
are located in the front wall proximate to the opening and beneath
the closure mechanism. A cover is positioned over the one or more
first perforations having a surface facing away from the bag and a
surface facing towards the bag. The bag further includes an
adhesive positioned proximate to the top of the bag.
[0008] Further, the present invention is a bag for storing
products. The bag includes a front wall, back wall, and a storage
space defined between the front wall and the back wall with an
opening at a top of the bag for inserting products into the storage
space. The bag includes a closure mechanism for closing the
opening. One or more first perforations are located in the front
wall proximate to the opening and beneath the closure mechanism for
permitting air trapped within the storage space to escape. A cover
is positioned over the one or more first perforations for sealing
the bag after air trapped within the storage space has escaped. The
cover is an integral extension to the front wall of the bag. The
cover includes a front surface facing away from the bag, a back
surface facing towards the bag, a top edge, a bottom edge, and two
side edges, with the bottom edge and the two side edges of the
cover being secured to the bag. An adhesive is secured to the bag.
One or more second perforations are above the one or more first
perforations, with a portion of the adhesive located between the
first and the second perforations.
[0009] Still further, the present invention is a bag for storing
products. The bag includes a front wall, a back wall, and a storage
space defined between the front wall and the back wall. An opening
at a top of the bag is for inserting products into the storage
space with a closure mechanism for closing the opening. One or more
first perforations are located in the front wall proximate to the
opening and beneath the closure mechanism for permitting air
trapped within the storage space to escape. A cover is positioned
over the one or more first perforations for sealing the bag after
air trapped within the storage space has escaped, with the cover
being a separate piece from the bag and including an adhesive
material.
[0010] Even further, the present invention is a method of expelling
air from a storage bag. The method includes the steps of applying
pressure to a closed storage bag filled with trapped air, so air
travels through perforations on a surface of the bag, breaking an
adhesive seal for the perforations, and exits through an opening to
atmosphere created by the breaking of the seal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a perspective view of a storage bag with a vent
cover being a separate piece from the bag.
[0012] FIG. 2 shows a cross-sectional view taken along line II-II
of FIG. 1.
[0013] FIGS. 3 and 4 show cross-sectional views, similar to the
view of FIG. 2, of other embodiments of the storage bag.
[0014] FIGS. 5 and 6 show another embodiment of a storage bag with
a vent cover being an integral piece of the bag, with FIG. 6
showing a cross-sectional view taken along line VI-VI of FIG.
5.
[0015] FIGS. 7 and 8 show an embodiment of a storage bag with a
chamber venting structure, with FIG. 8 showing a cross-sectional
view taken along line VIII-VIII of FIG. 7.
[0016] FIGS. 9 and 10 show another embodiment of a storage bag with
a chamber venting structure, with FIG. 10 showing a cross-sectional
view taken along line X-X of FIG. 9.
[0017] FIGS. 11 and 12 show another embodiment of a storage bag,
with FIG. 12 showing a cross-sectional view taken along line
XII-XII of FIG. 11.
[0018] FIGS. 13-17 show alternative embodiments for the
perforations.
[0019] FIG. 18 shows a method of expelling excess air from the
interior of a storage bag.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] With reference to the Figures, exemplary embodiments of the
present invention provide a venting structure for use in storage
bags in order to free air trapped inside the bag after products are
placed inside the bag and the bag is closed.
[0021] The exemplary embodiments of the present invention help to
alleviate the problem of desiccation, which is commonly referred to
as freezer burn, created by the presence of air and the build-up of
air pressure in the storage bag by providing vents on the bag. If
air pressure is increased inside the bag, vents operate to reduce
the air pressure by releasing the internal air out from the storage
bag and to the environment. In addition, the present invention
overcomes the problem created by air in the storage bag causing
excessive space to be taken up by the bag. Releasing air from
inside the bag through the vents will reduce the volume of the bag
and therefore conserve space.
[0022] As will be described, the design of the exemplary
embodiments of this invention provides multiple means by which
excessive air pressure can be expelled from the storage bag. As
illustrated in FIG. 1, and generally applicable to all embodiments,
a storage bag 5 may have a front wall 10 and a back wall 12 for
storing products. The bag 5 is designed to be re-closeable, and
re-sealable. Therefore, a consumer may use the bag 5 to store more
products once its current contents are depleted, or to obtain
access to the currently stored contents without having to re-store
them in another bag.
[0023] The bag 5 is preferably made of a plastic film. The term
"film" as used herein represents any three-dimensional material
which possesses two opposite facing surfaces separated by edging
surfaces. The opposite facing surfaces may be mono- or poly-planar
and the combined surfaces typically (and preferably) possess many
times the area of the edge surfaces. Films employed in the
manufacture of storage bags are typically polyolefin thermoplastic
films such as one or more layers of polyethylene (low density, high
density, linear low density, ultra low density and/or combinations
thereof), polypropylene, and polyethylene copolymers (low density,
linear low density, ultra low density, high density and/or
combinations). Polybutylenes, polyvinyl chloride (PVC),
polyvinylidene chloride (PVDC), ABS polymers, polyurethanes,
polycarbonates, polysulphones, aliphatic polyamides,
polyarylamides, polyaryletherketones, polyarylimideamides,
polyaryletherimides, polyesters, polyarylates, polyoxymethylene,
poly(epsilon-caprolactone), and the like, alone or composited with
a variety of materials, such as metal films, paper, cardboard,
textile structures, non-woven materials, wood, and the like may
also be used.
[0024] The structure of a re-closable, re-sealable bag 5 may be
accomplished by using one of several closure mechanisms, either
alone or in combination with one another. In the preferred
embodiment, an interlocking closure (ILC) 14 is used as the closure
mechanism for the opening of the bag 5. The ILC 14 is shown
somewhat schematically in FIGS. 1-11. Generally speaking, the ILC
14 includes a pair of fastening strips provided with inter-engaging
closure profiles. The interlocking fastening strips may be
manufactured by extrusion through a die and may be formed from any
suitable thermoplastic material including, for example,
polyethylene, polypropylene, nylon, or the like, or from a
combination thereof. Thus, resins or mixtures of resins such as
high-density polyethylene, medium-density polyethylene, and
low-density polyethylene may be employed to prepare the
interlocking fastening strips. When the fastening strips are used
in a sealable bag 5, the fastening strips and the films that form
the body of the bag 5 may be conveniently manufactured from heat
sealable material. In this way, the bag 5 may be economically
formed by using an aforementioned thermoplastic material and by
heat sealing the fastening strips to the bag 5. For example, the
bag 5 may be made from a mixture of high pressure, low-density
polyethylene and linear, low-density polyethylene. The fastening
strips may be manufactured by extrusion or other known methods. For
example, the closure device may be manufactured as individual
fastening strips for later attachment to the bag 5 or may be
manufactured integrally with the bag 5. In addition, the fastening
strips may be manufactured with or without flange portions on one
or both of the fastening strips depending upon the intended use of
the fastening strips or expected additional manufacturing
operations. Generally, the fastening strips can be manufactured in
a variety of forms to suit the intended use. The fastening strips
may be integrally formed on the opposing sidewalls of a container
or bag 5, or connected to the container by the use of any of
several known methods. For example, a thermoelectric device may be
applied to a film in contact with the flange portion of the
fastening strips or the base portion of fastening strips having no
flange portion, to cause a transfer of heat through the film to
produce melting at the interface of the film and a flange portion
or base portion of the fastening strips. Suitable thermoelectric
devices include heated rotary discs, traveling heater bands,
resistance-heated slide wires, and the like. The connection between
the film and the fastening strips may also be established by the
use of hot melt adhesives, hot jets of air to the interface,
ultrasonic heating, or other known methods. The securing of the
fastening strips to the film stock may be carried out either before
or after the film is U-folded to form the bag 5. In any event, such
securing may be done prior to side sealing the bag 5 at the edges
by conventional thermal cutting. In addition, the first and second
fastening strips may be positioned on opposite sides of the film.
Such an embodiment would be suited for wrapping an object or a
collection of objects such as wires. The first and second fastening
strips should usually be positioned on the film in a generally
parallel relationship with respect to each other, although this
will depend on the intended use.
[0025] Additional examples of suitable closure mechanisms include a
slider device that seals an interlocking closure, tape, hook and
loop fasteners, adhesives applied to the bag 5 near the mouth of
the bag 5, or an adhesive material formed integrally with the bag
itself, as described in U.S. Pat. No. 6,149,304, which is hereby
fully incorporated by reference in its entirety. Although the
present description focuses on the preferred ILC closure mechanism,
any of these alternative closure mechanisms may of course be
utilized.
[0026] As shown in the figures, the ILC 14 is located near a top
edge 16 of the bag 5. The ILC 14 is preferably integrally formed
with the rest of the bag 5, as described in U.S. Pat. No.
5,774,955, which is hereby fully incorporated by reference in its
entirety. The ILC 14 divides the front and back walls 10, 12 into
two parts, a flange or handle portion 18 located above the ILC 14
for gripping the bag 5, and a storage portion 20 located below the
ILC 14 for storing products in the bag 5. When the bag 5 is closed,
the ILC 14 creates an air-tight seal to the storage portion 20, so
that air, liquid, or the like cannot penetrate through the ILC
14.
[0027] In order to expel excess air from inside the bag 5 even when
the ILC 14 is closed, a venting structure is incorporated in the
bag 5. In the preferred embodiment, perforations 22 are formed in
the bag 5 to create an exit from the bag 5 for the excess air. As
shown in FIG. 1, the perforations 22 are located in the storage
portion 20 of the bag 5 and are formed in a straight-line
configuration. Representative alternative configurations for the
perforations 22 are shown in FIGS. 13-17, respectively, as X-shapes
22a, cross-shapes 22b, half-moons or C-shapes 22c, S-shapes 22d,
and discontinued circle shapes 22e. It is preferred that the
perforations 22 are cuts, incisions, or the like as shown in those
Figures, rather than holes in the bag 5, although either may be
used. The use of cuts greatly facilitates sealing of the venting
structure after excess air is expelled (as described further
below), and avoids producing waste bag material, such as a hole
would, during manufacture.
[0028] Varying the number and /or configuration of the perforations
22 may lead to different surface areas being available for excess
air to escape from the bag 5. One or more perforations may be used.
It is preferred, however, to have several perforations each
configured to have relatively short length cuts. Smaller-sized cuts
are easier to seal than larger-sized cuts because the opening of a
smaller-sized cut uses less surface area on the bag. Generally
speaking, the greater the surface area, the greater the potential
of leakage.
[0029] The perforations 22 preferably extend from one side of the
bag 5 to the opposite side of the bag 5. A tremendous convenience
in manufacturing storage bags is thus obtained when they are made
by forming, sealing, and separating a continuously running plastic
web film. The film roll moves in a machine direction (MD), defined
as the long direction of the film roll. A transverse direction (TD)
is defined as the short direction of the web film roll. If the
perforations extend all the way across the bag 5, there is no
specific location to find on the surface of individual bags along
the machine direction. Thus, for example, the perforations may be
formed in the moving film by a rotating die, pressure tool, or the
like disposed just above (or below) the film which rotates with the
movement of the film to create the perforations into the film,
preferably in the direction of film movement. This allows the
perforations to be easily placed along the entire width of the bag
without worry of registration between the subsequently formed side
seals.
[0030] A cover 24 may be placed over the perforations 22 to prevent
air from re-entering the bag 5 after the air has been expelled from
the bag 5, to discourage insects from possibly crawling inside the
bag 5, and otherwise to help prevent the contents of the storage
bag 5 from being contaminated. The cover 24 may be made from the
same material as the bag 5 or a material that will permit securing
by heat sealing, ultrasonic welding, etc. to the bag 5. In one
embodiment, as shown in FIGS. 1-4, the cover 24 may be initially
formed as a separate piece from the bag 5, and then attached as
follows.
[0031] As shown in FIGS. 1 and 2, a top edge 24a of the cover 24 is
heat sealed, ultrasonically welded, or otherwise permanently
secured to the bag 5 along with both side edges 24b of the cover
24. The top edge 24a of the cover 24 is permanently secured to the
top edge 16 of the bag 5. In an alternative configuration (not
shown), the top edge 24a of the cover 24 may be secured to the
front wall 10 of the bag 5 below its top edge 16, or even below the
ILC 14. A bottom edge 24c of the cover 24 has an adhesive strip 26
permanently secured to a surface of the cover 24 facing the bag 5.
The adhesive strip 26 allows the bottom edge 24c of the cover 24 to
be removably sealed to the front wall 10. The cover 24 also
includes a surface facing away from the bag.
[0032] Several different types of adhesive 26 may be suitably used
with the storage bags described here, depending on the intended use
of the bag 5. For example, if the bag is intended for use in
storing food products, the adhesive 26 is preferably a "food grade"
adhesive. A hot melt pressure sensitive adhesive is generally
acceptable. In particular, a pressure sensitive hot melt adhesive
may be used, such as the H.B. Fuller Company's product number
NW1007XZP. The adhesive used may be selected from a list of various
types such as styrene-butadiene-styrene (SBS) block copolymers,
acrylic based formulations, silicone based formulations or the
like. Additionally, the form may be hot melt types as well as
liquid emulsions, suspensions, or solvent formulae.
[0033] As the air is expelled from the bag 5 through the
perforations 22 when the cover is not sealed to the front wall 10,
illustrated by the arrows in FIG. 2, the air will enter the
atmosphere at an opening 28 near the bottom edge 24c of the cover
24. If the adhesive 26 is initially sealed to the front wall 10,
either the pressure of the air being forced from the inside of the
bag 5 will break the seal or the user can manually lift the cover
24 with his fingers in order to create the opening 28 to the
atmosphere. Once the air is expelled, the user may manually reseal
the adhesive 26 to the front wall 10 by applying pressure to the
cover 24 at points where the adhesive 26 has been applied. This
embodiment shows the adhesive 26 as being located directly on top
of and surrounding the perforations 22. The adhesive 26 may
alternatively be applied at any point along the surface of the
cover 24 facing the front wall 10 between the perforations 22 and
the opening 28. The adhesive 26 may similarly be permanently
secured to the front wall 10 for forming a removable seal with the
surface of the cover 24 facing the front wall 10. In the
embodiments described above in connection with FIGS. 2-3 and below
in connection with FIGS. 6 and 12, the amount of air pressure alone
that is needed to force a broad front break of the adhesive 26
overlying the perforations 22 can be significant. In practice, it
is contemplated that the user will manually lift the cover 14 to
break the seal and then squeeze the bag 5 to expel any trapped air
from within the bag 5 through the now exposed perforations 22. This
step is performed, of course, after the closure mechanism has been
closed.
[0034] In FIG. 3, the opening 28 to the atmosphere is adjacent the
top edge 24a of the cover 24 for the air inside the bag 5 to travel
through, as illustrated by the arrows in FIG. 3. The bottom edge
24c and side edges 24b of the cover 24 are heat sealed,
ultrasonically welded, or otherwise permanently secured to the bag
5. Adhesive 26 is permanently secured to the surface of the cover
24 facing the front wall 10 for removably sealing against the front
wall 10. As described with respect to the FIG. 2 embodiment, the
adhesive 26 need not cover the perforations, and the adhesive 26
may be permanently secured to the front wall 10 rather than the
cover 24. In this embodiment, however, the adhesive 26 is
preferably located at a distance from the perforations 22 (i.e., so
as not to directly overlay the perforations 22) in order to
facilitate the breaking of the releasable seal of the adhesive 26
by air pressure alone as the user is expelling trapped air from the
bag 5. By locating the adhesive 26 away from the perforations 22,
the user can more easily expel trapped air from the closed bag 5 by
simply squeezing the bag since a lower force is needed to break the
seal of adhesive 26 when it does not directly cover the
perforations 22. The force of air expelled through the perforations
22 acting against the overlaying adhesive-free portion of the cover
26 generates a peel force which acts on the adjacent portion(s) of
the cover 26 that are sealed to the front wall 10 by adhesive. The
location of the adhesive 26 from the perforations defines a peel
angle. In general, the peel angle is inversely related to the peel
force required to break the adhesive seal. That is, the higher the
peal angle, the lower the peal force required.
[0035] In FIG. 4, the top edge 24a and bottom edge 24c of the cover
24 create the opening 28 to atmosphere. The air can exit at the top
edge or at the bottom edge or at both edges simultaneously. Only
the side edges 24b of the cover 24 are heat sealed, ultrasonically
welded, or otherwise permanently secured to the bag 5. Adhesive 26
is permanently secured to the surface of the cover 24 facing the
front wall 10 for releasably sealing against the front wall 10, or
vice versa.
[0036] In the embodiment of FIG. 5, the cover 24 is formed as an
integral element of the bag 5, being an extension of the flange
portion 18 at a fold-over line 30. Because the cover 24 is extended
from the flange portion 18, the top edge or terminal edge 24a of
the cover 24 does not need to be secured to the bag 5. The air
escapes to the atmosphere from inside the bag 5 near the bottom
edge 24c of the cover 24, as illustrated by FIG. 6. Thus, this
embodiment operates substantially the same as already described for
the FIG. 2 embodiment.
[0037] FIGS. 7 and 8 illustrate an alternative embodiment referred
to herein as a chamber design of the storage bag 5. With respect to
the chamber design, a second set of perforations 220 may be
incorporated within the bag 5. The second set of perforations 220
function similarly to the opening 28 to the atmosphere as described
above. As illustrated in FIGS. 7 and 8, the chamber design may
include a cover 24 formed as an integral extension of the flange
portion 18 [reference numeral 18 is missing from FIGS. 7-8] which
is heat sealed, ultrasonically welded, or otherwise permanently
secured to the front wall 10 at the bottom edge 24c and side edges
24b of the cover 24. Thus a chamber 29 is formed. The first set of
perforations 22 is located below the ILC 14 and adhesive 26 so that
air may pass between the chamber 29 and the storage portion 20 of
the bag 5. The second set of perforations 220 is located along the
fold-over line 30 so that air may pass between the chamber 29 and
the atmosphere. Thus, when the adhesive 26 is not sealed to the
front wall 10, air is free to exit from inside the bag 5 through
the first set of perforations 22, travel into the chamber 29 up
past the adhesive 26, and then through the second set of
perforations 220 to the atmosphere.
[0038] After closing the bag 5 and expelling the excess internal
air from the bag 5 of FIGS. 7 and 8, the user may apply pressure to
the cover 24 at the ILC 14 to removably seal the cover 24 to the
front wall 10, thus closing the air flow path from the first set of
perforations 22 to the second set of perforations 220. In this way
the adhesive 26 is removably sealed with a single swipe from the
hands of a user across the top edge 16 of the bag 5, similar to the
method of closing the bag 5. Locating the second set of
perforations 220 along the fold-over line 30 allows for greater
ease in folding the cover 24 over the first set of perforations
22.
[0039] As discussed above, an advantage of the chamber design is
the reduced amount of force required to unseal the cover 24 from
the front wall 10 as the air exits the bag 5. In this embodiment,
as air is forced into the chamber 29 from the storage portion 20,
the air presses up against the side of the adhesive 26 seal between
the cover 24 and the front wall 10. Thus the force causing the
cover 24 to become unsealed and separate from the front wall 10 is
perpendicularly oriented to the direction of separation or "peel",
forming a "peel angle." Conversely, in the embodiment of FIG. 1,
when air is forced out of the perforations 22 it presses up against
the cover 24, so that the separating force is directed parallel to
the peel direction--in other words there is no "peel angle." One of
ordinary skill in the art will appreciate that it takes more force
overcome a broad front seal (i.e., where there is no peel
angle).
[0040] Although not illustrated in the Figures, there are several
similar alternative embodiments to the one shown in FIGS. 7 and 8.
For example, the second set of perforations 220 need not be located
exactly along the fold-over line 30, but may instead be located
anywhere in the cover 24 above the adhesive 26, or anywhere in the
front wall 10 above both the adhesive 26 and the ILC 14. Also, the
adhesive 26 may be permanently secured to the front wall 10 for
removably sealing against the cover 24, instead of permanently
secured to the cover 24 for removably sealing against the front
wall 10. Additionally, the adhesive 26 need not be located exactly
adjacent to the ILC 14. It may, for example, be located below the
first set of perforations 22 instead of above them as shown in the
Figures--in that case, the opening 28 to the atmosphere is located
below the adhesive 26, either as a second set of perforations 220
(similar to the ones shown in FIG. 7) or as a complete opening 28
(similar to the one shown in FIG. 2).
[0041] FIGS. 9 and 10 illustrate yet another embodiment of a
storage bag 5. This embodiment is substantially the same as the
embodiment of FIGS. 7 and 8, except that the second set of
perforations 220 is one perforation extending along the majority of
the top edge or terminal edge 24a of the cover 24. Functionally,
the storage bag 5 in FIGS. 9 and 10 is substantially the same
storage bag 5 in FIG. 3. However, the two bags are manufactured in
different ways.
[0042] FIGS. 11 and 12 illustrate a further embodiment of a storage
bag 5. In this embodiment, the top edge 24a and bottom edge 24c of
the cover 24 as well as only one side edge 24b of the cover 24 are
heat sealed, ultrasonically welded, or otherwise secured to the
front wall 10. Therefore, the opening 28 to the atmosphere is at
the opposite side edge 24b to the one that is heat sealed,
ultrasonically welded, or otherwise secured to the front wall 10.
The adhesive 26 is permanently secured to either the cover 24 or
the front wall 10 at some point between a set of perforations 22
and the opening 28.
[0043] In order to expel excess air from inside the bag 5 the user
may apply external pressure to the bag 5, typically with one hand
30a on the front wall 10 and the other hand 30b on the back wall
12, as shown in FIG. 18. The hands are moved together to push the
air pressure out of the bag. Other methods may be used to expel the
air pressure from the bag 5, but are not illustrated.
[0044] It is known to form small ribs extending longitudinally
across a storage bag 5 in its flange portion 18. Such ribs provide
easy gripping surfaces to help a user open the bag 5 when the ILC
14 is closed, and to carry the bag 5 from place to place. Such ribs
may of course be utilized in any of the embodiments described here.
They are most easily utilized with the embodiment of FIG. 5,
however, where the bag 5 may be made as a single piece of plastic
film.
[0045] Another beneficial feature of the embodiments of the storage
bag 5 is placing all closing and sealing components in close
proximity to each other, and in particular proximate to the opening
of the bag 5. The user automatically seals the perforations 22 with
the cover 24 and adhesive 26 when closing the bag 5 with the ILC
14. Even after expelling the air from the bag 5, the resealing of
the cover 24 is in a familiar area to the user.
[0046] Although the invention has been described in detail with
reference to certain preferred embodiments thereof, other
embodiments are possible. For example, the perforations 22 and
cover 24 may be placed at the bottom end or at a side of the bag 5.
Therefore, the spirit and scope of the appended claims should not
be limited to the description of the preferred embodiment contained
herein.
* * * * *